The larvae of the processionary caterpillar gather in bags hanging from the trees during the winter and as the month of February approaches it is normal for the crowns of the large pine forests to begin to open. characteristic white nests of the pine processionary caterpillar.
The descent of the processionary caterpillar to burrow itself and continue its metamorphosis normally took place in the months of April and May, but this has changed and is being brought forward due to the mild temperatures in recent winters caused by climate change.
The regional government of Murcia has launched a new phase of the battle plan land treatments to combat the pine processionary caterpillar in the mountains of the autonomous community. These performances start today in Calasparra, where they will last two days, and end on January 24 in Ricote.
Loose The treatments will be carried out in public forests with a large influx of visitorssuch as recreational areas and trails frequented by hikers, cyclists and families. Among the areas it is worth highlighting enclaves such as Cresta del Gallo, La Luz in the Regional Park of El Valle and Carrascoy, the Camino de la Pilgrimage in Torreagüera, the Sanctuary of the Virgin of Hope in Calasparra and the Recreation Area from La Salud in Lorca. In addition, the evolution of the pest will be evaluated in order to intervene in other areas.
The pine processionary caterpillar (Thaumetopoea pityocampa) is a forest pest adapted to the Mediterranean climate. In your In the third larval stage the caterpillars develop stinging hairs that can cause allergic reactions in humans and animals. During the winter months, especially February and March, the caterpillars descend to the ground in long ‘processions’ to bury themselves, completing their metamorphosis. This period poses the greatest health risk, as contact with the larvae can cause dermatitis, eye infections and even serious respiratory problems.
Less area for the procession
The The prolonged drought has weakened the forests, making them more vulnerable to processionary caterpillars and other harmful organisms. However, high temperatures can limit the pest (at more than 32 degrees the larvae suffer high mortality). The lack of rain also affects the availability of new needles, essential for their development.
Historically The affected area in the Murcia region has decreased significantlygoing from an average of 14,000 hectares per year in 2000 to less than 7,000 hectares now. However, infestation levels have increased in certain areas, with 50 percent of affected areas experiencing severe infestations.
Other factors, such as the transformation of forests into mature forest stands, mortality among young plantations as a result of drought and forest fireshave also influenced the dynamics of the plague. These actions have reduced areas historically vulnerable to processionary caterpillars.
Action plans
Loose Terrestrial treatments include misting with a spray gunof which the application of 0.35 percent cypermethrin is carried out using guns mounted on all-terrain vehicles to cover large areas quickly; manual spraying, through the use of backpack sprayers in hard-to-reach places; and manual bag removal, which consists of direct removal with pruning shears to prevent the spread of caterpillars.
The product used, Cypermethrin is a non-systemic insecticide approved by the Ministry of Agriculture, Fisheries and Food.. During work, the treated areas are marked and access is controlled to ensure safety.
This plan is part of a comprehensive program that combines preventive, biological and direct methods. More than 1,600 hectares were treated in November 2024 using a biological insecticide based on Bacillus thuringiensiswith an effectiveness of more than 90 percent. In addition, pheromone traps were installed between August and October to capture adult butterflies and monitor population density. Biological measures have been implemented such as the installation of nest boxes for insect-eating birds and shelters for bats, natural enemies of the processionary caterpillar, thus promoting sustainable control of the pest.
The Directorate General for Natural Heritage and Climate Action recommends that areas with visible nests or processions of caterpillarsespecially during sunny and windy days, when the risk of contact increases. Recommendations for the little ones include ensuring that they do not touch the caterpillars, and in case of contact with pets, you should go to the vet if you have any symptoms of inflammation or breathing difficulties; and in the case of garden owners: manually removing the bags, applying approved phytosanitary products or installing rings around the trunks to catch caterpillars.